I picked this a few weeks ago, the seller did tell me up front of the issue of not functioning 100 % of the time. I did find the feed lips worn and was allowing the rounds to slip past them at times. I was able to adjust them so that issue is fixed. The other issue is it would stove pipe or fail to go into full battery. Both were caused by the same problem. The chamber is tight, I am thinking on this pistol the chamber is not cut to the large side, but to the small side. I found after some testing and measuring 22 ammo that Federal, CCI and Winchester white box all fit and function 100%. CCI quite will load but not function as to little pressure to cycle. Remington full power are to big around at the boolit, case is OK. Now for the head scratchier, Remington subs will function as well.
I was surprised to find that Rem full power are so over sized. All the rest will pass the "plunk" test even with what I feel is a tight chamber. SAAMI specs show a .226, I measured a few spent cases and all came out at .225 to .226. I have in the past dump 22 ammo into a ammo can just freely, not anymore. My 22LR revolvers do not care, they like and shoot just fine for plinking with what ever I feed them. My 10/22s like and function as well with all the ammo I have.
This pistol is my first semi in 22LR and am learning as I go as to how to get to function 100%. I am looking for another mag or 2, I can find them on ebay and a few other sites. So far I can not find one like mine. The slot on the side at the top is what is missing on the ones I find. I really like this pistol, it is a hoot to shoot and hits where I point.